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arXiv · 1103.3914

Quantum corrections to the dynamics of the Bose-Einstein condensate in a double-well potential

Wei Fan·Yan Xu·Bing Chen
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Abstract

The dynamics of the Bose-Einstein condensate (BEC) in a double-well potential is of- ten investigated under the mean-field theory (MFT). This works successfully for large particle numbers with dynamical stability. But for dynamical instabilities, quantum cor- rections to the MFT becomes important [Phys.Rev.A 64, 013605(2001)]. Recently the adiabatic dynamics of the double-well BEC is investigated under the MFT in terms of a dark variable [Phys.Rev.A 81, 043621(2010)], which generalizes the adiabatic passage techniques in quantum optics to the nonlinear matter-wave case. We give a fully quan- tized version of it using second-quantization and introduce new correction terms from higher order interactions beyond the on-site interaction, which are interactions between the tunneling particle and the particle in the well and interactions between the tunneling particles. If only the on-site interaction is considered, this reduces to the usual two-mode BEC.

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Wei Fan, Yan Xu, Bing Chen. 2012-02-22. Quantum corrections to the dynamics of the Bose-Einstein condensate in a double-well potential. https://arxiv.org/abs/1103.3914

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